This invention relates to terminal housings of the type which are intended for use on electrical devices having coils thereon and which receive terminals that establish contact with the coil windings. The herein disclosed embodiment of the invention is particularly intended for use on the stator of an induction motor, however, other uses for the principles of the invention will be apparent to those skilled in the art of manufacturing electrical motors.
It is now common practice to form the electrical connections between lead wires and wires in a coil by the use of electrical terminals which have wire-receiving slots that are dimensioned to receive the coil wire and which penetrate the varnish type insulation of the coil wire to establish electrical contact therewith. Terminals of this type also have a means for forming an electrical connection with the lead wire which extends from the coil. U.S. Pat. No. 3,979,615 discloses a housing and a terminal which is adapted to be mounted on the stator of a universal motor, the terminal having wire-in-slot type connecting means which establishes electrical contact with the coil wires and a contact spring arm which serves to establish electrical contact with a lead wire. Application Ser. No. 849,049 filed Nov. 7, 1977 now U.S. Pat. No. 4,132,460, shows another type of terminal housing having an integral mounting means for forming electrical connections to coil windings.
While this wire-slot technique is now in widespread usage in many parts of the electrical industry such as in the manufacture of different types of electrical motors and the manufacture of induction coils, this technology has not been applied to the manufacture of conventional induction motors, probably because of space problems and other manufacturing problems which are associated with conventional induction motors. Current manufacturing practice for conventional induction motors requires that the ends of the coil windings be connected to the lead wires by crimping simple open U-type terminals onto the ends of the coil wires and the lead wires. The splices which are produced by the crimping operation are then insulated by assembling one or two insulating layers to the splices. Thereafter, the insulated splices are buried in the coil windings and the stators are dipped in a liquid varnish-type insulation. The stators are then baked to cure the insulation and thereafter the stators are assembled to motor housings. This manufacturing procedure is a relatively involved process requiring much handling and it results in a high reject rate when the stators are inspected after the baking operation. The handling required for the dipping and baking operations frequently results in disturbance to the electrical splices between the lead wires and the coil windings and the rejected stators must be scrapped or reworked to cure their defects and repair the damage which was produced during the handling period.
The instant invention is directed to the achievement of a terminal housing which can be mounted on the stator after it has been dipped in the liquid insulating material and baked so that the ends of the coil windings can be connected to the lead wires immediately prior to assembly of the stator to the motor housing. The terminal housing is mounted on the stator in a manner such that it is securely held in place after the stator is assembled to the motor housing and cannot be removed from the stator.
It is accordingly an object of the invention to provide an improved terminal housing for wires extending from electrical coils. A further object is to provide a terminal housing having integral mounting means which is intended to be mounted on the stator of an induction motor. A further object is to provide a terminal housing which will simplify and facilitate the manufacture of induction motors.